Coal coking and burning magazine stove



Patented Aug. 21, 1951 COAL COKING AND BURNING MAGAZINE STOVE John 0.Miles, Urbana, Ill., assignor to Board of Trustees, University ofIllinois, Urbana, Ill.

Application January 31, 1946, Serial No. 644,563

This invention relates to a coal stove or the like for heatingbuildings.

All bituminous coal contains large amounts of volatile matter which isnot burned completely in the ordinary stove or furnace and is given offin the form of smoke. This not only wastes much of the fuel value of thecoal but also results in a dirty atmosphere. Various methods have beenproposed for burning the combustible vapors. Most of these methods,however, are not adaptable to simple stoves for the heating ofresidences.

I have invented a light-weight, inexpensive stove which uses thedowndraft principle of burning to consume the smoke. This new stoverequires a minimum of attention and can be easily regulated so that theheat given off can be controlled. The new stove provides for a storagespace which can be filled with coal and will then require no attentionfor considerable periods of time.

With the new coal stove it is now possible to heat small homes emcientlyand at extremely low cost. All the combustible matter of the fuel isburned and there is very little or no smoke given off at any time.

The invention will be described as related to the embodiment of the sameset out in the accompanying drawings. Of the drawings Fig. 1

is a partial vertical section taken substantially through the center ofthe stove; Fig. 2 is a'horizontal section taken along line 2-2 of Fig.1; Fig. 3 is a horizontal section taken along line 33 of Fig. 1; Fig. 4is a horizontal section taken along line 4-4 of Fig. 1; and Fig. 5 is ahorizontal section taken along line 55 of Fig. 1.

The coal stove shown in the accompanying drawings comprises a shell ill,a base H, and an,

exhaust pipe I2 for the escape of burned gases. The shell I is ofsubstantially cylindrical shape except for a flat rear portion l3inclined downwardly and inwardly. This fiat rear portionextends fromnear the top to approximately the mid-portion of the shell.

On the inside of the shell there is located a flat plate l4 arrangedsubstantially parallel to and spaced from the flat rear portion l3 ofthe shell. This plate I4 is supported on four posts l and has its bottomend I6 extending into the stove. The top edge of the plate M is spacedfrom the top portion ll of the shell.

.At the top of the shell I9 there is located a radiator l-8communicating with the exhaust pipe l2. This radiator is separated fromthe firebox J9 that is located in front of the fiat plate l4.

7 Claims. (Cl. 126-73) Immediately beneath the lower edge of the flatplate Hi there is located a fiat grate 20 formed of three substantiallyrectangular grate bars 2|, 22, and 23. This grate defines the bottom ofthe firebox. 7

At the front of the stove there is located a combustion chamber 24formed of refractory elements 25 against the shell 10 and a second setof refractory elements 26 spaced from the first set 25. The top of thecombustion chamber 24 communicates with the radiator l8, while thebottom of the combustion chamber communicates with the firebox [9. Thebottom entrance to the combustion chamber 24 is formed by an inclinedshoulder 21 of refractory material extending beyond the inner edge ofthe combustion chamber and into the firebox. The inclined shoulder 21forms a constricted entrance 28 to the combustion chamber 24.

Secondary air is admitted upwardly to the combustion chamber 24 throughan air passageway 29 at the front of the stove and beneath the inclinedshoulder 21. This secondary air passageway is formed by refractory ormetal elements 30 held in spaced relationship from the shell I0. The topof the refractory elements 30 as shown is spaced from the shoulder 21and inclined inwardly and upwardly to form an air opening 31.

The bottom portion of the flat plate I4 contains a number of holes orperforations 32. These holes extend upwardly to a point substantiallyeven with the bottom of the refractory elements 26 forming thecombustion chamber 24. The rear inclined portion l3 of the shell [0contains air ports 32a and 321) with both ports covered by an adjustabledamp-er 33. The air ports 32a and 32b are formed by a division strip 14aextending across the fiat plate I4. Air enters the port 32a and flowsupwardly over the upper end of the fiat plate [4 and down along the flatplate into the under-grate portion 34 of the stove. The air flowsthrough port 32b, down along plate 14, through the holes 32, up throughthe grates 20, and up through the secondary air passageway 29 andopenings 31 and 28 into the combustion chamber 24. When the furnace isin operation and filled with coal the firebox I9 will be divided into acoke-burning zone 35 extending from the grates to the entrance 28 to thecombustion chamber 24, a coking zone 36 above the coke-burning zone 35,and an uncoked coal zone 31 above the coking zone 36. Air enters thecoke-burning zone 35 through the grates 20 around the bottom portion ofthe inclined plate [4 and through the lower holes 32. Air enters thecoking zone 36 through the upper holes 32. Air enters the uncoked coalzone 31 around the upper edge of the fiat plate I4. The top frontportion ll of the shell l adjacent this upper edge is provided with adownwardly extending flange 38 to direct the air in a generally downwarddirection through the uncoked coal zone 31.

At the top of the stove and beside the radiator l8 there is located anopening 39 for the introduction of coal into the firebox [9. Thisopening 39 is normally closed by a hinged door 40 that opens toward theradiator 18. This hinged door may be opened by means of a handle 4|.Adjacent the opening 39 is a second opening 42 between the firebox l9and the radiator 18. This second opening 12 is normally kept closed by asliding door 43 held in side brackets 44. The two doors 40 and 43 areconnected by a bar 45 hingedly mounted at one end on the first door 40and also hingedly mounted at the other end on the sliding door 43. Withthis construction the two doors are opened and closed substantiallysimultaneously.

Each of the grate bars 2 l, 22, and 23 which define the bottom of thefirebox are hingedly mounted at points beneath their mid-sections. Thefirst grate bar 2! at the front of the firebox is provided with arelatively short downwardly extending bar 48. The second grate bar 22 isprovided with a similar bar 4! of appreciably greater length, and thethird grate bar 23 is provided with a similar bar 58 of still greaterlength. The lower ends of each of these bars, 46, 41, and 48 arerotatably connected by an inclined bar 49. With this arrangement thegrates are shaken by moving the inclined bar :9 back and forth, by meansof any desired. mechanism. This movement rotates the grate bars 2:, 22,and 23, with the grate bar 2| being rotated through the greatest arc,the second grate bar 22 being rotated through the next greatest arc, andthe third grate bar 23 through the smallest arc. This construction isimportant because the greatest burning rate occurs at the front of thestove, and the grate bar 2| underneath this portion is given thegreatest agitation when the grates are shaken. As shown in the drawingsthe middle grate bar 22 is turned by a handle 59 extending through theshell l0, and this turns the other grate bars 2| and 23.

The under-grate portion of the stove is provided with an ash removaldoor at the front or back thereof. The radiator l8 has a top opening 52that is used for clean-out purposes, and this opening is normally keptclosed by means of a weighted cover 53.

When the furnace is in operation air enters through the air ports 32aand 32b. The air from port 32a is directed down through the uncoked coalzone 3?. The air from port 3222 is directed laterally into the cokingzone 36; another portion of this air is directed laterally into thecokeburning zone 35; a portion of the air is directed upwardly into thecoke-burning zone 35; and a final portion of the air is directed upthrough the secondary air passageway 29 around the shoulder 21, andthrough the constricted opening 28 into the combustion chamber 2 Theburning gases ordinarily extend through the combustion chamber 24 andinto the radiator 18. In this chamber all of the volatile combustibleproducts are consumed, leaving only the gases fromthe combustion to beexhausted out the pipe I2.

Having described my invention as related to the embodiment shown in theaccompanying drawings, it is my intention that the invention be notlimited by the details of description unless otherwise specified butrather be construed broadly within its spirit and scope as set out inthe accompanying claims.

Iclaim:

1. A coal stove comprising a shell having a front wall inclineddownwardly and inwardly; a plate arranged substantially parallel to saidfront wall for at least the greater part of its length and spacedtherefrom; a firebox behind said plate divided into a coke-burning zoneat the bottom thereof, a coking zone above said coke burning zone and anuncoked coal zone adjacent the top portion of said plate; said platehaving perforations therein communicating only with the cokeburning zoneand the coking zone; means forming an air port through said shellopposite said plate and above the coke-burning zone; a grate beneath thelower edge of said plate and forming the lower boundary for saidcoke-burning zone; means forming a combustion chamber above andlaterally displaced from the coke-burning zone; means for directing aportion of the air from said air ports downwardly into the uncoked coalzone; means for directing a portion of the air through saidperforations; means for directing a portion of the air upwardly into thecoke-burning zone; and means for directing a portion of air upwardly assecondary air into the combustion chamber.

2. The coal stove of claim 1 wherein the upper edge of said plate isseparated from the top portion of the shell to provide an air openinginto the top of the uncoked coal zone.

3. The coal stove of claim 1 wherein there is provided a constrictedneck portion of diminishing cross-section at the bottom entrance to thecombustion chamber through which the secondary air enters.

4. The coal stove of claim 1 wherein the top portion of the shellcontains a radiator separated from the firebox with the top of thecombustion chamber opening into said radiator on one side thereof and astack for burned gases communicating with an opposite side thereof.

5. The coal stove of claim 1 wherein the top of the firebox containsmeans forming an open-. ing for the introduction of coal normally closedby a door, and the top portion of the shell contains a radiatorseparated from the firebox with the top of the combustion chamberopening into said radiator on one side thereof and a stack for burnedgases communicating with an opposite side thereof, said radiator havingmeans forming an opening communicating with the firebox and normallyclosed by a door, said opening between the radiator and the fireboxbeing located beneath the stack.

6. In a coal stove and the like having a firebox formed with acoke-burning zone, the combination comprising: means forming acombustion chamber above one side of the coke-burning zone andcommunicating therewith at the bottom of the combustion chamber, abafile at one side of the coke-burning zone and beneath the combustionchamber with the bafile being spaced from the adjacent side of the stoveand the bottom of the combustion chamber to form an air passageway, andthe top edge of the bafile adjacent said side of the stove being slopedupwardly and inwardly, and a second baille having a portion projectingfrom the said side of the stove into the space between the first bafileand the bottom of the combustion chamber and spaced from each, saidsecond bafile having an upwardly and outwardly sloped top surfaceleading to the bottom entrance of the combustion chamber, the saidsloped top of the first baffle and projecting portion of the secondbafiie forming gradually diminishing constricted air entrances to thecokeburning zone and to the bottom of the combustion chamber.

7. The coal stove of claim 6 wherein the projecting portion of thesecond baflle extends beyond the inner surface of the first baflie andthe inner side of the combustion chamber.

JOHN C. MILES.

REFERENCES CITED UNITED STATES PATENTS Name Date Mayhew June 29, 1869Number Number Number 6 Name Date Livermore Mar. 11, 1890 Hinstin Feb.16, 1892 Benster June 1, 1897 Schumann Dec. 24, 1901 Boies et a1 Aug.30, 1910 Lazzell Dec. 12, 1916 Mersfelder May 11,1920 Wier Nov. 17, 1925Lowe Sept. 22, 1942 Wingert June 20, 1944 Wingert Dec. 4, 1945 Sanfordet a1 July 9, 1946 FOREIGN PATENTS Country Date Austria May 25, 1904Austria Aug. 26, 1934 Germany June 23, 1904 Great Britain June 18, 1928Germany Sept. 30, 1933

